Pressure-retaining valve



Jan. 17, 19281 1,656,811

H. H. ASKEW ET Al.

PRESSURE RETAINING VALVE Filed Aug. l, 1925 IE 1 E l- Patented Jan. 17, 1928.

UNET SET All ES:l

. Arr clerics.,

HARVEY H` ASKEW- AND JAMES H.V ASKEW, OF SAN BERNARDIN'O, GALIFORNIA`;'IDA N3. ASKEW ADMINISTRATRIXDE SAID JAMES' H. ASK'EW, DEGEASED';

ynnssUrcnLnnr-MNING vnnvna `Among the salient objectsfof our? inven;n

tion; is to'provide asimple andeiiicien't pressl the' purpose of retaining-- a; predeterminedi pressure. in thel brake cylinders afterl the] application of' the brakes,y and' whichv Willi thus put the 'complete'- control of the airv brakes offa railway train in thehands ofi the engineer; to providev such a pressure-retaining valve mechanism which can. bel readily` attached to* the triple valvev of an air brake'system and which Will automatiscally control the exhaust from said tripple valve; to provide in' a mechanism. of the character referred: to aslide valve adapted' to be operatedd by theV movement ofi an ele#- ment, or diaphragm, having tvvoE diierent air pressures against the opposite sides thereof, the varying otsaid'. pressurescausL ing the movement oi" said vlave; and", 1n general, to provide a simple and practical deviceoffthe character referred to.4

When used in connection with ani air brake'system cfa railwayftrain, said pres,` sure' retaining valve operatesI to vf hold a* pres determined pressure inl the brake cylinder While the engineer rechargesk the auxiliary reservoirafter the: application of@ the brakes. 'n orderto explain ourinventiomwve have illustrated one practicalJ embodiment thereof onV thel accompanying sheet of drawings,y in `WhlCll,- i

Figure 1 is a fragmentary' view showing ourk invention in connection with al brake pipe line,- triple I valve andf airk reseevoir;

Figure 2" is a vertical sectional view taken through ouriinvention as`v herev illustrated;

Figure 3' isf a sectional view taken Online 3L-3` ci4 Fig. 2f; and V Figurell-is'a sectional view taken on line 114-4 of Fig, 2i y Referring novv` to the" drawings, 1. designates a brake' pipe line, 2, the usual triple valve, and lan'4 air reservoir. v @ur improved retaining valve is designated as a Whole 4, and's is* shown attachedto the `side ot the triple valve. Referring to: Figa `2,0m' valve bodyv as liererepresentedg comprises a cast- *ino'f 5, adapted?" at 6, tok be connectedto` the ex aust ofthetriplevalve 2; saidI connection' connecting a bly-pass 8, around a vertical valve chamberQ; with a passageway, 10. A valve seat, 11", is arrangedy inZ the lower end ofthe-valve chamber, 9, upon which seats a flexible. valve,1 12, upon the upper: end ofi which. seats the loWerend of a; coiled spring\ 13, the upper-rend of which spring isanound a member 1d, in; a hollowI member 15, screwediintatheibodyoven said valve @hamsV ber 9, as indicated in Fig. 2. This spring, 13, yieldinglyx holds. thel valve 12,v seated upon,V the valve seat` .11, and thestrength4 oi the spring used determines the; pressure: necessary` to'A opens'saida valve.A Said valve chamber 9Il communicates throughL said valve` seat memberflihivvitha passageway'lO.. Saldi body is also provided atitslowerleft handi side; asseenin Eig: 2; Witln threaded inlet, openingg. as 16, connecting; wiith passageway, 1T, divided into: two branches, l asf 18 g and 19, connectingl with ai central chamben 2.0, in said body' 5,@ and lieneinaffter again referred to.. `Saidbody alsoi has atits lower right hand! iside, as here illustrated,l a. third threadeda opening;y as 21, terminating; at its upper end in a horizontal chamber, 22, closede by means-1 oli ai screw plug, 23having an. inwardly extending memberv 241, around which is: aI coiled spring,I 2.5. Mounted in the centrali chamber 20;. is au ningi member f having a diameter equal to' the.' vertical height o saidl chamber 20, said ring mem-.- ber being designated 26, andf havingf at its opposite sides tivo metal, discs,4 27 `and 28,.` between Which, Wit-hin said'v ring 26., is al tubulanshafped member 29.,.1nade halves, asf indicated bv` the dotted*v line: baclc of the memben', which. isi an; operating leverhthe loxver end of which"r is pivotally connected to a-nl anchor plug, 31" screwed: intoda threadedl opening; in thea lowerA side` of the ringL member 26,?. andi thezupper end: of, which lever'fits- 'mtoithe underside ot a slide*l valve member 32;.in ai horizontal chamber 33, With which communicates the,` passageway 10. Said: horizontal chamberv 38, is,Y closed. at, its opposite ends:1 Withi screw' plugs,` 3.4, 34, u with a= spring member, 35, therein, bearingk on said slidevalve32, as indicated.. Said: slidevvalfve its` inner end against the round' disc, 28.`

The4 tubular member 29, isapnovided. im its middleY portion Witlr two bearing members,

- 37, 37, bearing onfopposite sideso'f the valve operating lever, 30;. for movingsaidi lever VThus our pressure retaining valve body is connected by inea-ns of the threadedv member (5, Withithe exhaust oi the usual triple valve ot a brake system, member' 16, ot' our said valve is connected with a pipe line 1, by a branch pipe 1, which branch pipe 1, is also connected With the triple valve Y 2, `in the usual Way. ll`he threaded member 21 of our said` valve is connected by means of a pipe, 38, to the air reservoir, 3, which reservoir is also connected With way, as at 2.

lllithout our pressure retaining valve, when an engineer applies the air brakes and releases them, all the air which has passed 'from the reservoir to the `brake, cylinders, through the triple valves,.is .released and escapesl into the atmosphere through the exhaust of saidvtriple valve and is lost and there not suiiicient pressure in the reservoir to apply the brakes until a fresh supply The pressure 4from the brake has beenpumped into said reservoir, andthe engineer 1s helpless until the reservoir 1s again filled. With our invention,

connection at- 6, into the by-pass 8, and the passageway 10, and if the pressure is suiiiinto the chamber 9, and can escape through an outlet at 15', in the hollow member 15. pipe line, 1, being connected with the threaded member 16, and bearing against the disc, 27, in the central` chamber' 20, `forces the member 29, and the valve `operating lever 30, and the slide valve 32, to the right, as shown in Fie. 2, and this closes the outlet port 36, and prevents the exhaust 'from the triple valve from escaping therethrough; The pressure in the reservoir, being connected to the member 21, bears against the opposite disc, 28 but until the reservoir pressure hasbeen raised, it'is not suiiicient t-o move the me1nber,29, and the operating lever 30 and slidevalve 32, to the lett, and thereby open the outlet port 3G. `The spring 25, which bearsv against the disc, 28, is forthe purpose of overcom ing therfriction of the moving parts only.

Thus the pressure from the brake pipe line, connected `at 16, and the pressure from the auxiliary reservoir 3, connectedat21, bear against the opposite sides ofthe diaphragnncomposedoiI the discs 27 und 28, and the member 29, to move the `operating lever 30, and the slide valve 32, to control said discs, 27 and 28, to permit -condensation anything of thelind to escape from `Within the member 29, or between said discs, as is on its pivotback and forth to move the slide 'valve in the upper part of the valve body.

while the threaded the triple valve in the usual this air from the exhaust is discharged through the cient, it operates the valve 12 and passes the exhaust port at 36. Drain openings, as 19 and 21 areprovided atthe lower sides of r device to Ythe atmosphere, said.` secondl `valve heldin the device, and only partial release ofthe brakes.accomplished, until the reservoir is again recharged by the engineer. When this is done, the pressure operates to move the opposite side of thediaphragm and to, open the slide valve 32, and then there is a full release. rlhus a predetermined brake cylinder pressure is retained by our device, depending on the spring 13, used te hold the Avalve 12, untilthefreservoir is re charged. This" gives the engineer iull control and enables him to again apply the brakes in emergency after they `have been applied and released. y

hilc We have shown and described one practical 'embodiment oir our invention on theaccompanymg sheet of dravvings,ive are aware `that changes 1n details of construe .tion and arrangement can be made Without `secure `by triple valve, of an automatic pressure retainr.

ing valve interposed therein and connected with the exhaust, a valve member therein adaptedto hold said exhaust, and i adiaphragm operated by the pressure in said reservoiry and` valve member to open position, Whereb when said reservoir pressurefis `increase said valve member is moved and said e2;- haust yis released. i

connected for `moving saidl 2. In an air brake system, `combination with the brake pipe line, `reservoir and triple valve, of an automatic pressure retaining valve interposed therein and connected .with the exhaust of said triple valve, a

spring pressed valve member thereinfor holding said exhaust pressure, a slidevalve member adapted to hold said 3exhaust"pressure, and a diaphragm operatedby pressure from the reservoir and connected forfmov ingsaid slide valve membertobpen said exhaust pressure 'to the atmosphere.

3. In an air' `brake system, in combination With the bralre pipe line, reservoir and triple valve, a pressure ,y retaining, device interposed therein and connectedto `receive the exhaust after the application of "said brakes, a spring pressed valve thereinfor holding said exhaust pressure in said device, and a second valve movable to open said being normally held closed by air pressure from the brake pipe line, and a division p diaphragm whereby increased pressure in said reservoir operates to move said second valve to open said device to the atmosphere and release said exhaust pressure.

4. In combination with an air brake system, a pressure retaining device connected therein to receive the exhaust therefrom after the application of the brakes, and a valve member in said device connected to be operated by increased pressure in said air brake system, whereby to open said exhaust and cause complete release of said air brakes, said valve being operated by a division diaphragm operatively connected to operate said valve.

5. In combination with an air brake system and the reservoir, a pressure retaining device connected to the exhaust, a spring controlled valve therein controlling exhaust from said device, a slide valve therein controlling a second exhaust from said device,

and a division diaphragm for operating said slide valve, said diaphragm being controlled and operated by increased pressure in said reservoir, whereby said increased pressure operates to open said slide valve and said exhaust, substantially as described.

6. In combination with an air brake sys tem, the triple valve and reservoir, of a pressure retaining device connected to said triple valve to receive the exhaust, and a valve therein controlling exhaust therefrom, said valve being connected to be operated to the open position by increased pressure in said reservoir, said operating connection including a dead end chamber with a movable part connected to said valve.

Signed at San Bernardino, San Bernardino County, California, this 24th day of July, 1925.

HARVEY H. ASKEW. JAMES H. ASKEW. 

